Question: Simplify the following expression: $y = \dfrac{9x}{8} - \dfrac{x}{3}$
Explanation: In order to subtract expressions, they must have a common denominator. The smallest common denominator is the least common multiple of $8$ and $3$ $\lcm(8, 3) = 24$ $ y = \dfrac{3}{3} \cdot \dfrac{9x}{8} - \dfrac{8}{8} \cdot \dfrac{x}{3} $ $y = \dfrac{27x}{24} - \dfrac{8x}{24}$ $y = \dfrac{27x -8x}{24}$ $y = \dfrac{19x}{24}$